Answer: I'm Confused. You didn't specify if there were 6/5 ratio of parents or if there were 6/5 ratio of students. No matter, if there are 6/5 ratio of parents to students then there is 24 more parents. If there are 6/5 ratio of students to parents then there is 24 more students.
Explanation:
I got this answer by dividing 120 by 5 which equals 24. Now if there is 6/5 you would have to add another 1/5 to the 5/5. So it would be 24 + 24 + 24 +24 +24 (which = 120) plus anther 24 to get 6/5. so there is 24 more (students or parents [made unclear]).